RESUMEN
The Barbatimão is a tree which bark is rich in tannin. It is used on popular medicine as a wound healing agent, in the treatment of gastric lesions, as anti-leishmanial agent and as anti-inflammatory. Red blood cells (RBC) are labeled with technetium-99m (Tc-99m) and are utilized in many procedures in nuclear medicine. Some authors have reported that drugs (natural and synthetic) can alter the labeling of RBC with Tc-99m. This study evaluates the effect of barbatimão infusion on the labeling of red blood cells (RBC) and plasma (P) proteins with Tc-99m. Heparinized blood from Wistar rats was incubated with NaCl 0.9 percent as control and different concentrations of barbatimão infusion. Following the addition of stannous chloride (SnCl2), as reducing agent, and Tc-99m, as sodium pertechnetate, the blood samples were centrifuged. P and RBC were separated and were also precipitated with trichloroacetic acid 5 percent. Insoluble (IF-P and IF-RBC) fractions were isolated. The percentage of radioactivity in all the samples was determined. All the barbatimão infusion concentrations decreased the labeling of RBC, IF-P and IF-RBC. We can speculate that the barbatimão infusion interfered on the labeling of RBC due to the redox properties and/or it can also act as a chelator of the stannous ion.